HU197035B - Polyolefin composition with tensile strength of 8-30 mpa and impact-tensile strength of 80-500 kj/square metre - Google Patents

Abstract

Polyolefin compsns. of guaranteed quality and good compatability made from variable constituents contain 100 pts. wt. polyolefin and/or polyolephin scrap, 1-20 pts.wt. elastomer based on thermoplastic amorphous atactic polypropylene and ethylene-propylene-copolymer and/or ethylene-propylene-diene-terpoly mer and vulcanised in dynamic conditions with peroxide, 0.01-10.0 pts. wt. antioxidant, 0.01-30.0 pts.wt. zeolite, 0-10 pts.wt. light-stabiliser and 0-100 pts.wt. known filler, reinforcing or other additive.

Description

The present invention relates to a polyolefin composition having a tensile strength of 8 to 30 MPa and a tensile strength of 80 to 500 kJ / m ² .

Making waste containing various polyolefin grades recyclable is an extremely important task, as the vast majority (about three quarters) of consumer plastic waste is made of polyolefins (Technical Economics Bulletin 22, 1201, 1981). The different types of polyethylene (low, high, medium density, linear low density, giant molecular weight) and polypropylene (homopolymers and statistical and block copolymers) are incompatible (Wenig, W., Meyer, K: Colloid and Polymer Science 258, 1009 , 1980), Plochocki, AP: Polyolefin blends: rbeology, melt mixing and applications, Ch. which is also evident from the changes in the properties of mixtures of different compositions, e.g. of high density and low density polyethylene and polypropylene, the HVAC system has a lower elongation at break than any of its pure constituents and is always below the additive rule, that is, its given numerical value (J) can be given by: J = xxji, where X | and jj is the mass fraction and characteristic of constituent i (Robertson, R.E., and Paul, D.R., Journal of Apolecular Polymer Science, 17, 2579, 1973).

This finding holds true for various polyolefin-based systems, as well as their impact strength and even tensile strength values. (Irovinger, A. J.) Williams, M. L.: Journal of Applied Polymer Science, 25, 1703, 1980); Gieco, R., Mucciariello, G., Ragosta, G., & Martuscelli, E .: Journal of Materials Science 15, 845, 1980).

The low ductility of the polyolefin blends (low tensile elongation, no neck formation on specimen failure), low tensile strength and impact strength, and poor overall accessibility.

Their impact strength, as a function of their composition, gives a minimum curve, unlike the straight line expected under the additive rule, and their tensile strength is fundamentally different from the additive one. The scarring sites formed by the collision of melt flows are also very weak, with failure always occurring here (Nolley, E., Barlow, J.W., Polymer Engineering and Science 20, 362, 1980; Bartlett, D.W., Barlow, J.W., Paul, DR). Journal of Applied Polymer Science 27, 2351, 1982).

Because the above difficulties require an increase in overall accessibility, crystalline ethylene / propylene based block copolymers, rubbers, have been found to be the most suitable additive (Lindsay, GA, Singleton, CJ, Carman, Ch. J., Smith, RW: Polymer Preprints 19, 206 , 1978; Nolley, E., Barlow, J.W., Paul, DR: Polymer Engineering and Science 20, 364, 1980; Bartíett, D.W., Barlow, J.W., Paul, DR: Joürnai of Applied Polymer Science 27, 2351, 1982; 1 English Patent No. 154,447.)

This result is not surprising because in ethylene / propylene-based crystalline rubbers the length <- * z

The ethylene segments according to the invention form a polymer which tends to crystallize, which is naturally well compatible with polyethylene, while the amorphous ethylene / propylene segments provide good compatibility with polypropylene. Namely, during the polymerization of impact-resistant polypropylene copolymers, a suitable particle size amorphous ethylene / propylene phase is "incorporated" into the polypropylene matrix.

The ethylene / propylene-based block copolymers are the most suitable according to the literature, since they form bridges, which are incorporated into the polypropylene and polyethylene phases. Despite the use of this type of compatibility enhancer at relatively high concentrations (e.g., 20% by weight), the specimens containing the fusion sites have insufficient strength, ductility, impact and tensile strength, and failure at the fusion site. relatively small (less than 15%) elongation.

The above experience was obtained with the use of crystalline ethylene / propylene block copolymers as enhancers because the addition of amorphous ethylene / propylene copolymer rubbers did not increase ductilylation. Therefore, crystalline ethylene / propylene copolymer rubbers (Nolley, E., Barlow, J.W., Paul, DR: Polymer Engineering and Science, 20, 364 (1980).

A further difficulty is that the physical-mechanical properties (ductility, tensile-tensile strength, etc.) of polyolefin mixtures depend on the processing conditions, and in particular on the choice of tool temperature, which are likely to affect the morphological structure (Nolley, E., Barlow). , J.W., Paul, DR: Polymer Engineering and Science, 20, 364, 1980 and Barthett, D.W., Barlow, J.V., Paul, DR: Journal of Applied Polymer Science, 27, 2351, 1982).

This means that each blend composition requires time-consuming and costly investigations to determine the most appropriate processing conditions.

Summarizing the state of the art, it is known that it is not known to add a compatibility additive to mixed polyolefins or their wastes which would result in increased tensile strength of the blends and increased impact strength due to good compatibility, which would also allow the melt flows to collapse in solids.

The object of the present invention is to overcome the drawbacks of the prior art, i.e. to provide a polyhedrine composition having improved compatibility and therefore increased tensile and impact strength.

The present invention is based on the discovery that the above object can be achieved by adding to the polyolefins of various compositions a thermoplastic rubber having a thermoplastic properties in the form of amorphous, atactic poly-2J-lipropylene 35-70% by weight and 65-30% by weight. It also contains ethylene / propylene gauze / or ethylene / propylene / diene terpolymer rubber as well as 100% conventional antioxidants and fillers.

The resulting composition has improved tensile and impact tensile strength due to its improved compatibility.

Namely, it has been found that the tensile and impact tensile strength of the polyolefin composition in any of the compositions of the invention is in accordance with the additivity rule when 2 to 20% by weight of said thermoplastic dynamic vulcanizer is added.

A further advantageous feature of the composition of the invention is that the product of the polyolefin composition doped as described above has a plastic deformation tendency that is comparable to that of the product without the seam weld.

These findings are surprising to the person skilled in the art because it was not expected in the prior art that an amorphous, in addition to atactic polypropylene, and even partially vulcanized elastomer would contribute to the compatibility of the material containing various polyolefin species and thereby to its physical-mechanical properties. repairs. According to the state of the art, the addition of the amorphous additive should have had the opposite effect, according to the literature references, otherwise only crystalline ethylene / propylene rubbers have been considered as compatibility additives. Furthermore, it was not expected that the amorphous thermoplastic dynamic vulcanizate could be used as a universal compatibility additive in any polyolefin composition, and when applied, any additive, tensile and impact tensile strength could be enforced. It would have been expected that each polyolefin composition would require a different thermoplastic dynamic vulcanizate composition, not that a dynamic vulcanizate containing atactic polypropylene and ethylene / propylene co- and / or ethylene / propylene / diene rubber would be universally applicable also to increase the compatibility of polyolefin blends which do not contain isotactic polypropylene. Due to its melt viscosity and partial crosslinking properties, the dynamic vulcanizate used as a compatibility enhancer was expected to induce phase separation phenomena in the processing operations, which would cause shrinkage and seam strength.

The composition according to the invention is prepared by mixing a mixture of polyethylene, polypropylene and optionally an additive with a dynamic vulcanizate and then homogenizing the mixture, preferably in an extruder.

No. 189266. The monomers are randomly distributed in ethylene / propylene rubber (EPM) and ethylene / propylene / diene rubber (EPDM) in a dynamic vulcanizate prepared according to Hungarian Patent Application No. 5,302,50. In EPDM rubber, the diene monomer may be ethylidene norbomene or dicyclopentadiene or 1,4-hcxadiene and may be present in the terpolymer up to 5% by weight.

Atactic polypropylene (APP) in the dynamic vulcanizate is a very low crystalline type (less than 5 wt.%) And high molecular weight (average molecular weight M "5X10"). The dynamic vulcanization of the PPE and EPM and / or EPDM rubbers according to Hungarian Patent Application No. 189,266 is a heat-degradable pcroxld compound, preferably dtkamyl-pcro> id. tert-butyl peroxide, 1,3-bis (tert-butylperoxyisopropyl) benzene, butyl 4,4-bis (tert-butyl-eroxyl) valerate.

Mordenite, clinoptilolite, natural mineral zeolite, or mineral trace elements containing such natural trolites, and partially amorphous molecular sieves of type X, Y, faujazite, faujazite, and mixtures thereof, are preferred.

As an ultraviolet light stabilizer, Stabinform c. magazine 2k. No. 2 66-67. (1977); their derivatives, sterically hindered aniline-containing stabilizers and mixtures thereof.

Suitable fillers and reinforcing materials are carbon black, doromite flakes, perlite, fly ash, alumina, chalk, limestone! yeast, quartz flour, fiberglass, pearls, talc or mixtures of these may be used advantageously.

Suitable excipients are paraffin oil, instrument oil, stearic acid salts and amides, dyes, pigments, and mixtures thereof.

The main advantages of the composition according to the invention are as follows:

a} Increased tensile strength and impact strength compared to the starting policlefines.

b) Improved tensile properties compared to the starting polyolefins (tensile seam tends to exhibit large plastic deformation).

c) Waste can be used as a polyolefin, and by making it recyclable, significant import savings can be achieved while simultaneously eliminating environmental pollution.

The composition and preparation of the invention are illustrated by the following examples.

Example 1 parts by weight of high density polyethylene (M '= 1,9X13; next melt index at 190 ° C, 48.5 N load 1.6 decigram / min), 10 parts of low density polyethylene (M _n - 1.2x10' having a melt index of 48 decigrams [dg] / min) and 7.5 parts by weight of isotactic polypropylene homopolymer (M „= 6 6.8X10, having a melt index of 3.5 dg / min) and 7.5 parts by weight of polypropylene copolymer (ethylene comonomer 5 wt. % polypropylene copolymer = »5.2X10, melt index: 7.5 dg /

-3,197,036 min) was washed, washed and dried (masterbatch). Subsequently, 0.5 parts by weight of 2,2-methylene-bis (4-methyl-6-tert-butylphenol) (Origrostab 2246, product of the Borsod Chemical Plant), 0.5 parts by weight of natural zeolite with a particle size of less than 200 µm were added. (Zeovit-RCLM-00, a product of the National Ore and Mineral Mines with a clinoptilolite content of 40-50% by weight) and 5, 10 and 5%, respectively. 15 parts by weight of an amorphous, thermoplastic, granular, dynamic vulcanizate which is disclosed in U.S. Patent No. 189,266. Hungarian Patent Application according to the following composition:

a part by weight of a terpolymer of ethylene / propylene / ethylidene-nobomene having a constituent ratio of 68: 28: 4 in the above order (EPDM further denoted by Dutral Space 038 EP, product of Montepolymer), part by weight of ethylene / propylene copolymer hereinafter referred to as EPM, Dutral Co 054, a product of Montepolimeri), in which the composition ratio is 1: 1

59.9 parts by weight of atactic polypropylene (M "=

5.6 X10 ³ , crystalline fraction: 2% by weight) (hereinafter referred to as APP, Tipplen APP-C, product of the Tisza Chemical Plant)

1.5 parts by weight of ZnO

0.5 parts by weight of a NaA molecular sieve with a particle size of less than 200 µm

1.5 parts by weight of 1,3-bis-tert-butyl peroxyisopropylbenzene (Perkadox 14/40, product of Noury).

The mechanically blended materials were homogenized and granulated in a melt extruder. Specimens containing weak spots in the granulate were injected. One specimen was made with a unilateral film inlet (A) in the same direction as the longitudinal axis, the other (B) with a double film inlet in the same direction with the longitudinal axis (point of collision), and the third (C). Specimens were provided as reference samples of the masterbatch with an ethylene / propylene block copolymer (ethylene: propylene ratio 70:30, M = 7X10 ³ , melt flow index 0.19 dg / min) (Vestopren TP 2047, manufactured by Hüls) and / or with amorphous EPDM canopy (Dutral Square 038 EP, product of Montepolimer), injection molded. The tensile strength (o _H ), elongation at fracture (ε _Η ) and elongation (s) of injection molded specimens as well as the tensile strength of the specimens (A) and the elongation at fracture at time t (ε) up.

The data in Table 1 clearly demonstrate that the tensile strength and impact strength of the composition of Example 1, even when measured on weak specimens, are superior to its starting masterbatch and reference samples.

Example 2

Blends of polyethylene and polypropylene homopolymers were prepared as described in Bartlett et al., Journal of Applied Polymer Science 27, 2352 (1982), and in the following compositions, from which plates were pressed for the assays described above. A thermoplastic amorphous, dynamic vulcanizate having the following composition was used as a compatibility additive:

45.00 parts by weight EPDM (same as example 1)

55.00 parts by weight APP (same as example 1)

10.00 parts by weight of limestone flour

10.00 parts by weight of dolomite flour 5.00 parts by weight of glass fiber 0.50 parts by weight of tetrakis (2,4-di-tert-butylphenyl) -4,4'-biphenylene diphosphonite (Sandostab P-EPO, manufactured by Sandoz)

Zeolite containing 10.00 parts by weight of fanjazite and having an amorphous content of 98% by weight (particle size: less than 250 pm)

2.25 parts by weight of ZnO

1.20 parts by weight of dicumyl peroxide

The following amounts of the above thermoplastic dynamic vulcanizate were added to a mixture of high density polyethylene and polypropylene. The tensile strength and impact strength of the mixtures were compared with the values reported in the literature.

The blend containing 25% by weight of high density polyethylene (Example 1) and 75% by weight of isotactic polypropylene (Example 1) without additive has a tensile strength of 26.2 MPa. The addition of the thermoplastic dynamic polyolefin vulcanizates of the above composition in amounts of 10 and 20% by weight results in a change of the above values to 28.2 and 27.3 MPa.

In the starting additives, the blend has a breaking strength of 38 kJ / η, which increases to 168 and 195 kJ / m ² after mixing 10 and 20% by weight of dynamic vulcanizate.

The base blend of 75 wt% high density polyethylene (Example 1) and 25 wt% polypropylene (Example 1) had a tensile strength of 21 MPa in additive-free form, having 10 wt% Epcar 847 (70:30 w / w ethylene-zpropylene copolymer). k later) to 18.7 MPa with a 20 wt% addition of 16.5 MPara (Comparative Example).

When the same amount of thermoplastic dynamic vulcanizate was introduced, the above values were 22.5 and 21.2 MPa, respectively. The initial blend has an impact strength of 46 kJ / m ² , which is 10 and 10%, respectively. With the addition of 20% by weight of exemplary thermoplastic dynamic vulcanizate, it increased to 295 and 340 kJ / m ² . Epcar 847 (70:30 ethylene / propylene ratio, M '- 8.1X10', melt flow index 1.2 dg / min) used as reference. Dynamic volcanizates 10 and 20% by weight -41. táblázó. '

Characteristics of the mixtures tested under tensile and impact stress

Typical Unit Test Example Composition Example 1 Comparative Comparative Comparative Type __________

5%% 10% 15%% 5% 101% 15%% 5% 10% 151% 101% additive-dynamic vulcanizate crystalline E / P copolymer with amorphous EPDM-amorphous and crude. kanosukkal, am. ratio 1: 4

Oh MPa. THE 22.8 21.7 21.5 20.1 19.8 18.9 21.2 19.1 18.9 21.4 20.1 B 22.6 21.1 21.4 20.1 19.6 17.7 21.0 19.5 17.6 21.3 20.2 C 22.9 21.5 21.7 20.2 20.3 17.8 21.0 19.6 18.3 21.6 20.5 · ε π % THE 8.8 14.4 10.1 6.6 7.1 8.8 6.6 7.1 9.1 8.8 6.6 B 9.1 10.5 10.3 6.6 7.1 8.8 6.6 7.1 8.8 8.8 6.6 C 8.8 9.1 9.3 6.6 8.8 8.8 6.6 7.1 8.8 8.8 6.6 Eb % THE 92.0 60.0 81.0 45.0 48.0 > 1.0 37.0 47.0 50.0 48.0 31.0 B 90.0 95.0 116.0 39.0 46.0 73.0 40.0 40.0 48.0 53.0 30.0 C 58.0 '85.0 75.0 31.0 54.0 62.0 35.0 40.0 37.0 47.0 44.0 THE kj / m ^: THE 500.0 410.0 390.0 420.0 310.0 B 460.0 390.0 360.0 390.0 280.0 C 490.0 370.0 360.0 380.0 320.0 ε % THE 66.0 53.0 48.0 51.0 45.0 B 74.0 49.0 46.0 49.0 40.0 C 71.0 49.0 49.0 49.0 40.0

with the addition of n, the impact strength values were 250 and 295 kJ / m ² , respectively.

Example 3 g

Extruded polypropylene homopolymer (M "- 6.6X10 ', melt flow index 1.4 dg / min). (Tipplen H 791 F, product of the Tisza Chemical Plant) and ₁₀ of low density polyethylene of extrusion type (M M = 8.2X10 ³ , melt index 0.05 dg / min). (Tipolen FA 2210, product of the Tisza Chemical Plant).

Mixtures of 95: 5, 90:10 and 80:20 wt.% Were prepared on a Brabender plastograph. The impact strengths of the sheets pressed from the blends 5, when tested in accordance with DIN 53 448 at 23 ° C, were 63, 78 and 83 kJ / m ² and at -20 ° C 30, 71 kJ / m ² - and values. 20

When a crystalline ethylene / propylene-based block copolymer (Vststoprcn TP 2047, product of Hüls) (Example 1) was used as a compatibilizer additive in 5% by weight, the values measured at 23 ° C were 69, 84, 90, respectively. , while those measured at 25-20 C were 33, 59, 80 kJ / m ³ .

If as a compatibility additive Taur Technical Rubber Factory Tauropren PP type is a thermoplastic polyolefin-based dynamic vulcanizate with the composition - 30

APP (Same as Example 1) 41.2% EPDM (Same as Example 1) 36.6%

Zeolite 35 (same as Example 1) 20.0 wt% antioxidant (same as Example 1) 2.2 wt%

The blends containing 5, 10 and 20 wt% low density polyethylene having 40 and 95, 90 and 80 wt% polypropylene homopolymers had tensile strengths at room temperature of 29, 26.7 and 25.9 MPa, respectively.

The above values were modified to 29.3, 27.5 and 26.8 MPa, respectively, when Tauropren PP was blended.

When Vcstopren TP 2047 (cf. Example 1) was used as data, the same values were reduced to 28, 25.8 and 24.7 MPa, respectively.

Example 4

A low density polyethylene (Example 3) and polypropylene (identical to Example 1) blend was prepared to give a 60:40 weight ratio having a tensile strength of 7.6 MPa and a tensile strength of 240 kJ / m '. When modified at 2 and 5% by weight with Tauroprin PP of the composition described in Example 3, the tensile strength was 8.0 and 8.5 MPa and the impact strength was 270 and 320 kJ / m ^{2, respectively} . in your vehicle.

Claims

Claims (2)

1. 8-30 MPa tensile strength and 80 to 500 kJ / m 'impact tensile strength of the composition containing a mixture of a copolymer consisting of polyethylene and polypropylene or an ethylene / propylene, characterized in that 5-90 parts by weight (1-9) ³ Xl0 average molecular weight low density and / or (5-20) X10 'average molecular weight, high density polyethylene and 95 to 10 parts (4-10) having an average molecular Xl0 ⁴ homopolknert polypropylene or copolymer thereof with an ethylene / propylene mixture, 0-5 parts by weight of a known additive, preferably filler, stabilizer and 2-20% by weight of rubber based on the total weight of the above polymers and additives - 30-65% by weight of atactic polypropylene, 65-30% by weight of ethylene / propylene copolymer and / or It is made by dynamic vulcanization of a mixture of ethylene / propylene / diene terpolymer containing by weight of diene and a quantity of 100% by weight of an additive, preferably a filler, an antioxidant, and a peroxide compound. Composition according to claim 1, characterized in that it contains zeolite having a particle size of up to 200 µm as a filler. Without drawing Kintija of the National Office for Inventions Λ responsible for publishing: Zoltán Himer Head of Department Published by: Technical Publisher Antikva Kft.